TEHRAN (Tasnim) - The UN-Arab League envoy Lakhdar Brahimi arrives in Damascus for talks with Syrian government officials, amid reports of fierce fighting in and around the capital city.

In his visit, which starts on Monday, Brahimi is expected to meet Syrian President Bashar al-Assad and Foreign minister Walid al-Muallem.

Brahimi has been trying to build support for peace talks planned in Geneva next month between the government and the opposition.

The so-called Geneva II peace talks, backed by Russia and the US and due to take place on November 23, have been repeatedly postponed amid wrangling among the Syrian opposition, and a dispute over which countries, including Iran, should participate.

Making the task harder for Brahimi has been the refusal of 19 powerful rebel groups in Syria to take part in the conference, saying that negotiating with the Assad government would be an act of betrayal.

They gave warning in the statement, posted online on Sunday, that anyone who attends such talks would be committing "treason, and ... would have to answer for it before our courts".